Judy McGrath, one of the architects of MTV, is stepping down as chairman and CEO of MTV Networks, positions she has held since 2004. MTVN parent Viacom said a successor would not be named. AdAge/ MediaWorks: McGrath began her career with MTV as a copywriter at the fledgling music-video channel in 1981, the year it began. NYT: The sudden change ended the tenure of one of the most powerful women in television and stunned many of the company’s employees at a time when MTVN — which includes channels like MTV, Comedy Central, Nickelodeon and VH1 — is riding a surge in both ratings for its programs and profits for its parent company, Viacom. LA Times: Many in the industry had speculated that McGrath would be forced out after Viacom chairman Sumner Redstone in 2006 fired Tom Freston from his job as Viacom chief executive. But McGrath held on, striking a working relationship, albeit uneasy at times, with Freston’s successor, Philippe Dauman. THR: What McGrath and a handful of others pioneered and then reinvented multiple times over the past three decades was not only an amalgam of youth-skewing channels, websites, merchandise, and programming, but more importantly a culture and state of mind. NY Post: He wants his MTV. With the departure of McGrath, Dauman is seizing the opportunity to solidify his grip on the company’s profit center.